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Makes 🢒 Chevrolet 🢒 1997 🢒 Corvette 🢒 Brakes 🢒 ABS Brakes - Delco/Bosch 🢒 DTC C1274 TCS Prime Valve Malfunction

Object Number: 95882 Size: SF
ABS Components
ABS/TCS Schematics

Circuit Description

The TCS Prime valve solenoid circuits are supplied with battery power when the ignition is in the ON position. The EBTCM controls the valve functions by grounding the circuit when necessary.

Conditions for Setting the DTC

The EBTCM senses a discrepancy such as an open, short to ground, or short to voltage in the circuit.

Action Taken When the DTC Sets

A malfunction DTC is stored, ABS/TCS is disabled and the ABS and Traction Control Indicators are turned ON.

Conditions for Clearing the DTC
    • Condition for DTC is no longer present and scan tool clear DTC function is used.
    • Fifty ignition cycles have passed with no DTC(s) detected.

Diagnostic Aids
    • Make sure the integrity of the connection between the EBTCM and the BPMV is secure, tight, and free from corrosion.

Test Description

The numbers below refer to step numbers on the diagnostic table.

  1. Checks the resistance value of the solenoid.

    2.

  2. Checks for a short to ground in the BPMV.

    3.

  3. Checks for an internal short to voltage.

DTC C1274 TCS Prime Valve Malfunction

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check

2
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the EBTCM connector.
  3. Remove the EBTCM from the BPMV.
  4. Inspect the EBTCM to BPMV connector for conditions which could cause intermittents such as damage, corrosion, or poor terminal contact.

Are internal connectors OK and cavity free of brake fluid?

--

Go to Step 3

Go to Step 6

3
  1. Install J 41247 BPMV Pinout Box to the BPMV connector.
  2. Using J 39200 DMM, measure the resistance between J 41247 terminals 4 and 7.

Is the resistance within the range specified in the value(s) column?

8 - 12ohms

Go to Step 4

Go to Step 8

4

Using J 39200 DMM, measure the resistance between J 41247 terminal 4 and the BPMV case.

Is the resistance within the range specified in the value(s) column?

OL (infinite)

Go to Step 5

Go to Step 8

5
  1. Remove J 41247 .
  2. Reinstall the EBTCM to BPMV.
  3. Reconnect the EBTCM connector.
  4. Turn the ignition switch to the ON position, engine OFF.

Does DTC C1274 reset as a current DTC?

--

Go to Step 9

Go to Step 7

6
  1. If connector corrosion or damage are present, replace BPMV and/or EBTCM as necessary.
  2. If brake fluid is present, replace both the BPMV and EBTCM.

Is the repair complete?

--

Go to Diagnostic System Check

--

7

Using a scan tool in ABS/TCS Special Functions run the AUTOMATED Test.

Does DTC C1274 reset as a current DTC?

--

Go to Step 8

Go to Diagnostic System Check

8

Replace the BPMV. Refer to Brake Pressure Modulator Valve .

Is the replacement complete?

--

Go to Diagnostic System Check

--

9

Replace the EBTCM. Refer to Electronic Brake and Traction Control Module .

Is the replacement complete?

--

Go to Diagnostic System Check

--